Vitamin B-12 is needed for normal nerve cell function, to combat fatigue and for the production of SAMe, a substance that helps regulate mood. B-12 is so important to our well being that researchers at the National Institute on Aging studied the relationship between B-12 deficiencies and depression in elderly women.

In this study, 700 disabled but otherwise healthy independent women 65 years and older were assessed for depression and B-12 deficiency. In women with mild to severe depression, researchers found a significantly lower level of B-12 than in nondepressed women. In fact, of the 122 women with severe depression, 27% showed significant B-12 deficiency.

Researchers have also determined that B-12 plays a key role in maintaining cognitive function. At the Department of Geriatric Medicine at the University Medical Centre in the Netherlands, researchers studied 16 independent healthy older women, each with preexisting B-12 deficiency. The women were studied for a total of six months: the first month taking a placebo, the remaining five months taking a B-12 supplement. Before and after the trial period, the women performed a variety of cognitive tests. The results showed the women had improved cerebral and cognitive function after the B-12 supplementation.

While vitamin B-12 can be obtained from meat, poultry, fish, eggs and dairy products, it is recommended that people 50 years and older take a B-12 supplement. This is because almost half of all people over 50 have a reduced ability to absorb nutrients from their food. Taking a multivitamin, a B-complex vitamin or B-12 alone should compensate.

Sources: J Gerontol A Biol Sci Med 2001 Dec;56(12):M775-9; Am J Psychiatry 2000 May;157(5):715-2